Ingot mold insert mat



Apnl 26, 1960 H. D. sTERlcK INGOT MOLD INSERT MAT Filed Dec. 12, 1957 FIG. 2

FIG. 1

FIG.- 4

vFIG. 3

FIG. G

FIG. 5

INVEN TOR. HARRISUN D. STERICK BY M, wmv

This invention is for an expendable mat to be used in the bottom of an ingot mold and is for an improved mat designed to reduce the cost and expense of such mats and to reduce their weight. The present application is a continuation-in-part of my application Serial No. 463.888, filed October 22, 1954, now Patent 2,855,644, issued October 14, 1958.

As pointed out in my application above identified,l

ingot mold insert mats are commonly formed by Wrapping one or more strips into a flat "pancake type of coil. Sometimes one of the strips is corrugated to give increased thickness and thus produce a mat with fewer convolutions of metal, and at the same time form a more effective chill mat. While the corrugations in the strip enable the mat to be wound with fewer convolutions, the use of corrugated metal does not reduce weight as much as desired, since there is a greater weight of metal in a linear foot of corrugated strip metal than there is in a linear foot of straight strip. These mats are of the order of sixteen or more inches in diameter, and their weight is considerable, making them expensive to ship and to handle.

An object of the present invention is to substantially cheapen and lighten the weight of the mat while providing a mat adequate for the purpose. This is accomplished by using one strip of metal coiled with a strip of fibrous, preferably consumable fibrous materiaL'preferably but not necessarily thicker than the metal. The fibrous material keeps the metal convolutions spaced and aids in forming the coil, while at the same time it closes the space between the convolutions to prevent the hot metal from irnpingng directly on the mold bottom at the beginning of the pour.

Other objects and advantages of my invention will be seen fromthe detailed description thereof in conjunction with the accompanying drawings, in which:

Fig. 1 is a more or less diagrammatic plan view of a mat embodying my invention;

Fig. 2 is a side elevation of a mat made according to my invention, a fragment being shown in section;

Fig. 3 is a view similar to Fig. 2 showing a slightly modified construction;

Fig. 4 is a view similar to Fig. 2 showing still another modification;

Fig. 5 is a fragmentary vertical section of still another modification; and

Fig. 6 is a fragmentary view in vertical section showing the application of a water repellant coating over the mat.

My invention, as above indicated, comprises a strip 0f metal coiled with a non-metallic spacer which may be rope, paper, boxboard, corrugated boxboard, all of which are organic consumable materials, but it may also be of asbestos or woven glass fibers. Referring rst to Fig. l, the mat is designated as 1, 2 designates a metal strip which is wound into a spiral together with a non-metallic filler 3, this filler starting at the center and terminating at 4, the metal strip being welded to itself at 5.

In the form of invention shown in Fig. 2, the mat,

2,933,788 PatentedApL 26, 1969.

designated 1, has convolutions of sheet metal 6 with a rope-like expander 7 between the convolutions, this ropelike expander being any one of the materials above specified, i.e., organic fibers, twisted rope, asbestos rope, fiber glass, or the like. 'Ihe metal convolutions may be Wound tight enough' to slightly flatten the rope, or the rope may be round or flattened. It is preferably thicker in diameter than the thickness of the metal strip.

Since the fibrous material weighs very much less than the metal, the mat is much lighter than an all-metal mat. In this particular embodiment the rope is positioned near the bottom of the strip only, leaving channels between the metal convolutions above the rope. The rope, if made of combustible material, will of course char when the ingot is poured, but it will protect the mold bottom or stool from the initial impact of the molten metal and the steel strip holds the fibrous material in shape and aids in imparting the initial chill to the first metal poured.

In Fig. 3, the mat 1 is of the form described and the metal strip is designated 8. The expander 9 between the metal convolutions in this case is a strip or superimposed strips of cardboard, boxboard, corrugated boxboard, paper, laminated paper, woven fiber glass, asbestos cloth, or combinations of these materials, and it is at instead of round. It is here shown as being less than the full width of the metal and-at the bottom of the mat. In Fig. 4 the construction is the same, 10 being the strip metal, and 11 being the expander which is like that in Fig. 3, but it is here shown between the top and bottom edges of the mat, and in both Figs. 3 and 4 the thickness of the expander is preferably greater than that of the metal. Y

In Fig. 5 the expander is like that in Figs. 3 and 4, but is coextensive in width with the metal. In this gure 12 are the metal convolutions, and 13 the convolutions of expander material.

There is always danger that mats made with nonmetallic fibers may be exposed to water in transit, in storage, on the shop floor. Water in the fibers could produce an explosion in the ingot mold when the mat is contacted with hot metal. I am therefore careful to use dry expander material and immediately after the mats are formed they are dipped into or sprayed with a waterproofing chemical or compound, such as lacquer, waterrepellant mold coating, grease, microcrystalline wax, oil or the like. 'I'his is indicated in Fig. 6 where 13 designates a mat of any of the forms described herein with a coating 14 over and enveloping its entire surface, this beiuga water-repellant, water-excluding or non-wetting material. Even a preformed plastic envelope which is tough enough to stand handling may be used if properly sealed.

In the drawings I have shown the metal as being a smooth strip, but if desired it may be roughened, etched, orV corrugated to more firmly retain the fibrous filling. Also, in the drawings, which are illustrative, the liber is thicker than the metal. While this is not necessary, it is desirable for the purpose of reducing weight and cost, but without impairing the purpose of the mat so long as there is sufficient metal to prevent the fibrous material from being instantly torn apart by the impact of the hot metal being poured onto it from a substantial elevation. The projected area of the mat when viewed face on there fore presents a greater area of fibrous material than metal.

I claim:

1. An ingot mold insert mat formed partly of fibrous material and partly of metal, the metal and fibrous material being in elongated strips coiled together into a spiral with the fibrous material confined between the convolutions of metal and substantially closing the space between the convolutions of metal, the metal serving t0 chill the molten metal and to reinforce the brous material and keep it in place under the initial impact of pouring hot metal into a mold in the bottom of which the mat is placed.

2. An ingot mold insert mat as dened in claim g1 vin which the fibrous material is of combustible substance.

3. An ingot mold insert mat as dened in claim 1 in which the mat is encased in a non-adsorbent water-repellant envelope.

4. An ingot mold insert mat as dened in claim 1 -in which there is a water-repellant coating on the brous material.

t v f4 References Cited in the le of this patent UNITED STATES PATENTS 

